// Problem: 
// Contest: 
// URL: 
// Memory Limit: 
// Time Limit: 
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#include<bits/stdc++.h>
using namespace std;
#define int long long
inline int read(){
	int s=0,w=1;
	char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-')w=-1;ch=getchar();}
	while(ch>='0'&&ch<='9') s=s*10+ch-'0',ch=getchar();
	return s*w;
}
signed main()
{
	int t=1;
	cin>>t;
	while(t--)
	{
		int n,ans=0;
		cin>>n;
		vector<int> v(n+1);
		for(int i=0;i<n;i++)cin>>v[i];
		string s;
		cin>>s;
		for(int i=0;i<n;i++)
		{
			if(s[i]=='>'&&v[i]<=0)
			{
				ans++;
				v[i]=1;
			}
			if(s[i]=='<'&&v[i]>=0)
			{
				ans++;
				v[i]=-1;
			}
			if(s[i]=='Z'&&v[i]*v[i-1]<=0)
			{
				ans++;
				v[i]=v[i-1];
			}
		}
		cout<<ans<<endl;
	}
	return 0;
}
